This patch fixes hard-coded value for the size of a chunk that includes
disk header for persistent snapshot. It should be changed to existing
macro NUM_SNAPSHOT_HDR_CHUNKS instead of using hard-coded value 1.

Any more places too? (E.g. persistent_commit_merge)
Alasdair

I think the expression in persistent_commit_merge should be changed to:
ps->next_free = area_location(ps, ps->current_area) +
ps->current_committed + 1;
It is numerically the same, but will avoid trouble if
NUM_SNAPSHOT_HDR_CHUNKS is increased.
Mikulas